Hodgkin lymphoma (formerly, Hodgkin disease) is a potentially curable lymphoma with distinct histology, biologic behavior, and clinical characteristics. The disease is defined in terms of its microscopic appearance (histology) and the expression of cell surface markers (immunophenotype).
There are 5 types of Hodgkin lymphoma classified by the World Health Organization (WHO) (Jaffe, E S, et al Eds. World Health Organization Classification of Tumours: Pathology and Genetics of Tumours of Haematopoietic and Lymphoid Tissues. Lyon France: IARC Press; 2001). Nodular sclerosing, mixed cellularity, lymphocyte depleted, and lymphocyte rich are the 4 types referred to as classical Hodgkin lymphoma (cHL). The fifth type, nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), is a distinct entity with unique clinical features and a different treatment paradigm.
Classical HL (cHL) is a monoclonal lymphoid neoplasm that in almost all instances appears to be derived from post-germinal center B cells. The immunohistochemical (IHC) hallmark of HL tumor cells is CD30 antigen expression. The morphological phenotype of cHL comprises an unusually small number (<2%) of mononuclear Hodgkin (H) cells and multinucleated Reed-Sternberg (RS) cells residing in an extensive inflammatory background, which is mostly composed of T cells, histocytes, eosinophils, plasma cells, and macrophages. This inflammatory background in the tumor microenvironment is maintained by Hodgkin's and Reed-Sternberg cell (HRS)-derived chemokines and cytokines that recruit the tumor microenvironment cellular components. The composition of the tumor microenvironment or the molecular phenotype of the HRS cells, or both, is thought to determine the relative aggressiveness of cHL at an individual level. (Gharbaran et al., “Fibroblast growth factor-2 (FGF2) and syndecan-1 (SDC1) are potential biomarkers for putative circulating CD15+/CD30+ cells in poor outcome Hodgkin Lymphoma patients.” Journal of Hematology & Oncology, 2013, 6:62)
In classical Hodgkin lymphoma, the neoplastic cell is the Reed-Sternberg cell, which is a large, abnormal lymphocyte that may contain more than one nucleus. (Thomas, R K et al, Part I: Hodgkin's lymphoma-molecular biology of Hodgkin and Reed-Sternberg cells. Lancet Oncol. January 2004; 5(1): 11-18; Re, D, et al, Molecular pathogenesis of Hodgkin's lymphoma. J. Clin. Oncol. Sep. 10, 2005; 23(26): 6379-86) Reed-Sternberg cells comprise only 1-2% of the total tumor cell mass. The remainder is composed of a variety of reactive, mixed inflammatory cells consisting of lymphocytes, plasma cells, neutrophils, eosinophils, and histiocytes. Reed-Sternberg cells consistently express CD30 (Ki-1) and CD15 (Leu-M1) antigens. CD30 is a marker of lymphocyte activation expressed by reactive and malignant lymphoid cells. CD15 is a marker of late granulocytes, monocytes, and activated T-cells not normally expressed by cells of B lineage.
Nodular Sclerosing Hodgkin Lymphoma (NSHL)
In NSHL, which constitutes 60-80% of all cases of Hodgkin lymphoma, the morphology shows a nodular pattern. Broad bands of fibrosis divide the node into nodules, and the capsule is thickened. The characteristic cell is the lacunar-type Reed-Sternberg cell, which has a monolobated or multilobated nucleus, a small nucleolus, and abundant pale cytoplasm.
Mixed-Cellularity Hodgkin Lymphoma (MCHL)
In MCHL, which constitutes 15-30% of cases, the infiltrate is usually diffuse. Reed-Sternberg cells are of the classical type (large, with bilobate, double or multiple nuclei, and a large, eosinophilic nucleolus). MCHL commonly affects the abdominal lymph nodes and spleen. Patients with this histology typically have advanced-stage disease with systemic symptoms. MCHL is the histologic type most commonly observed in patients with human immunodeficiency virus (HIV) infection.
Lymphocyte-Depleted Hodgkin Lymphoma (LDHL)
LDHL constitutes less than 1% of Hodgkin lymphoma cases. The infiltrate in LDHL is diffuse and often appears hypocellular. Large numbers of Reed-Sternberg cells and bizarre sarcomatous variants are present.
LDHL is associated with older age and HIV-positive status. Patients usually present with advanced-stage disease. Epstein-Barr virus (EBV) proteins are expressed in many of these tumors. Many cases of LDHL diagnosed in the past were actually non-Hodgkin lymphomas, often of the anaplastic large-cell type.
Lymphocyte-Rich Classical Hodgkin Lymphoma (LRHL)
LRHL constitutes 5% of cases. In LRHL, Reed-Sternberg cells of the classical or lacunar type are observed, with a background infiltrate of lymphocytes. It requires immunohistochemical diagnosis. Some cases may have a nodular pattern. Clinically, the presentation and survival patterns are similar to those for MCHL.
Nodular Lymphocyte-Predominant Hodgkin Lymphoma
Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) constitutes 5% of Hodgkin lymphoma cases. It is a distinct clinical entity and is not considered part of the classical Hodgkin lymphoma. Typical Reed-Sternberg cells are either infrequent or absent in NLPHL. Instead, lymphocytic and histiocytic (L&H) cells, or “popcorn cells” (their nuclei resemble an exploded kernel of corn), are seen within a background of inflammatory cells, which are predominantly benign lymphocytes. Unlike Reed-Sternberg cells, L&H cells are positive for B-cell antigens, such as CD20, and are negative for CD15 and CD30. A diagnosis of NLPHL needs to be supported by immunohistochemical studies, because it can appear similar to LRHL or even some non-Hodgkin lymphomas.
Etiology
The etiology of Hodgkin lymphoma is unknown. Infectious agents, particularly Epstein-Ban virus (EBV), may be involved in the pathogenesis. Depending on the study, data show that up to 30% of cases of classical Hodgkin lymphoma may be positive for EBV proteins. (Staal, S P, et al, A survey of Epstein-Barr virus DNA in lymphoid tissue. Frequent detection in Hodgkin's disease. Am. J. Clin. Pathol. January 1989; 91(1): 1-5). In addition, a case control study supports an increased risk of classical Hodgkin lymphoma after EBV infection, with a risk of approximately 1 in 1000 cases. (Hjalgrim, H., et al, Characteristics of Hodgkin's lymphoma after infectious mononucleosis. N. Eng. J. Med. Oct. 2, 2003; 349 (14): 1324-32) The incidence of EBV positivity varies with subtype. Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) rarely expresses EBV proteins (Weiss, L M, et al, Epstein-Barr virus and Hodgkin's disease. A correlative in situ hybridization and polymerase chain reaction study. Am. J. Pathol. December 1991; 139(6): 1259-65), whereas in classical Hodgkin lymphoma, EBV positivity is most common in the mixed-cellularity variant. (Pallesen, G et al., Expression of Epstein-Ban virus latent gene products in tumour cells of Hodgkin's disease. Lancet: Feb. 9, 1991; 337 (8737): 320-322). However, the exact mechanism by which EBV can lead to Hodgkin lymphoma is not known.
HIV-positive patients also have a higher incidence of Hodgkin lymphoma compared to HIV-negative patients. However, Hodgkin lymphoma is not considered an AIDS-defining neoplasm.
Genetic predisposition plays a role in the pathogenesis of Hodgkin lymphoma. Approximately 1% of patients with Hodgkin lymphoma have a family history of the disease, and siblings of an affected individual have a 3- to 7-fold increased risk of developing the disease. (Goldin, L R et al, Familial aggregation of Hodgkin lymphoma and related tumors Cancer, May 1, 2004 100(9): 1902-1908). Most evidence for a genetic etiology has been established in the distinct subtype of nonsclerosing Hodgkin lymphoma (NSHL). NSHL has been shown to be one of the most heritable types of neoplasm with a 100-fold increased risk in identical twins. Harty, L C et al, HLA-DR, HLA-DQ and TAP genes in familial Hodgkin disease. Blood, Jan. 15, 2002; 99(2): 690-93; Mack, T M et al, Concordance for Hodgkin's disease in identical twins suggesting genetic susceptibility to the young-adult form of the disease. N. Engl. J. Med. Feb. 16, 1995; 332(7): 413-18).
There is evidence that NSHL may result from an atypical immune response to a virus or other trigger, and that an atypical immunogenic response is involved. (Mueller, N E and Grufferman, S. Hodgkin lymphoma. InSchottenfield, D., Fraumeni, J F, Jr. Eds. Cancer Epidemiology and Prevention. New York, N.Y.: Oxford Univ. Press; 2006: 872-97). For decades, there have been known specific human leukocyte antigen (HLA) class II genotypes, including HLA-DRB1 and HLA-DQB1, that are associated with NSHL, and this has been confirmed by genome-wide association studies. (Cozen, W et al, A genome-wide meta-analysis of nodular sclerosing Hodgkin lymphoma identifies risk loci at 6p21.32. Blood. Jan. 12, 2012; 119 (2): 469-75; Enciso-Mora, V et al, A genome-wide association study of Hodgkin's lymphoma identifies new susceptibility loci at 2p16.1 (REL), 8q24.21 and 10p14 (GATA3). Natl Genet. December 2010: 42(12): 1126-30) Several single-nucleotide polymorphisms in the 6p21.32 region, which is rich in genes associated with immune function, have also been associated with NSHL risk. (Cozen, W et al, A genome-wide meta-analysis of nodular sclerosing Hodgkin lymphoma identifies risk loci at 6p21.32. Blood. Jan. 12, 2012; 119 (2): 469-75).
The Ann Arbor classification has been used to describe the stage of Hodgkin disease at initial presentation. This classification was modified to modify the classification in light of experience and new techniques for evaluating disease. As a result, it was recommended that computed tomography (CT) was included as a technique for evaluating intrathoracic and infradiaphragmatic lymph nodes; the criteria for clinical involvement of the spleen and liver be modified to include evidence of focal defects with two imaging techniques, and that abnormalities of liver function be ignored; that the suffix “X” be introduced to designate bulky disease (greater than 10 cm maximum dimension); and that a new category of response to therapy, unconfirmed/uncertain complete remission [CR[u]] be introduced to accommodate the difficulty of persistent radiological abnormalities of uncertain significance. (Lister, T A, et al, J Clin. Oncol. November 1989; 7(11): 1630-36). The Cotswolds modified Ann Arbor staging system for Hodgkin lymphoma is shown in Table 1. Regions of lymph node involvement are denoted by an E designation. The A and B designations denote the absence or presence of symptoms, respectively; the presence of symptoms correlates with treatment response.
TABLE 1The Cotswolds modified Ann Arbor stagingsystem for Hodgkin lymphomaStageArea of InvolvementISingle lymph node groupIIMultiple lymph node groups on same side of diaphragmIIIMultiple lymph node groups on both sides of diaphragmIVMultiple extranodal sites or lymph nodes and extranodal diseaseXBulk >10 cmEExtranodal extension or single, isolated site of extranodal diseaseA/BB symptoms: weight loss >10%, fever, drenching night sweats
In addition to the stage of the disease, many factors contribute to the likelihood of survival from Hodgkin lymphoma. The following table, which includes data from 3 organizations (the German Study Hodgkin Lymphoma Study Group (GSHG), European Organization for Research and Treatment of Cancer (EORTC), and the National Cancer Institute of Canada (NCIC)), shows examples of unfavorable risk factors for stages I and II.
TABLE 2Unfavorable Risk Factors for Stages I and II Hodgkin LymphomaRisk FactorGSHGEORTCNCICAge≧50 y≧40 yHistologyMC or LDESR or B symptoms>50 if A or>50 if A or>50 or any>30 if B>30 if BB symptomsMediastinal mass*MMR > 0.33MMR > 0.35MMR > 0.33or > 10 cmNumber of nodal sites>2>3>3Extranodal lesionsAny*Mediastinal mass is measured on chest x-ray by the mediastinal mass ratio (MMR), which is defined by the following: maximum width of mass/maximum intrathoracic diameter.Constitutional symptoms, e.g., unexplained weight loss (>10% of total body weight), unexplained fever, night sweats, collectively are known as B symptoms.ESR = erythrocyte sedimentation rate; LD = lymphocyte depletion; MC = mixed cellularity.
TABLE 3Stage Distribution and 5-Year Relative Survival by Stageat Diagnosis for All Races and Both Sexes: 2002-2008Stage5-year RelativeStage at DiagnosisDistribution, %Survival, %Localized (confined to primary site)1890.0Regional (spread to regional lymph4191.0nodes)Distant (cancer has metastasized)3775.7Source: National Cancer Institute. SEER stat fact sheets: Hodgkin lymphoma. Available at: http://www.seer.cancer.gov/statfacts/html/hodg.html. Accessed: Feb. 20, 2014
Based on these criteria, patients are classified as follows:    Early-stage favorable HL (includes patients with stage I or II HL and no risk factors by GSHG/EORTC or NCIC)    Early-stage unfavorable HL (includes patients with stage I and II HL and one or more risk factors)    Advanced-stage HL (includes patients with stages IIB, III, and IV)
Patients with advanced disease are further risk stratified using the International Prognostic Score (IPS), which includes the following risk factors (for each present factor, the patient receives 1 point) (Hasenclever, D and Diehl, V, “A Prognostic score for advanced Hodgkin's disease. Intl prognostic factors project on advanced Hodgkin's disease, N. Eng. J. Med. November 1998; 339 (21): 1506-14):    Albumin <4 g/dL    Hemoglobin <10.5 g/dL    Male    Age ≧45 y    Stage IV disease    Leukocytosis: white cell count (WBC)>15,000/μL    Lymphopenia: lymphocyte count <8% of WBC count and/or absolute lymphocyte count <600 cells/μL
Based on the IPS score, patients with advanced disease can be categorized as follows:    Good risk (IPS 0-1)    Fair risk (IPS 2-3)    Poor risk (IPS 4-7)
Although the International Prognostic Score was introduced to improve the risk stratification of patients, its applicability is limited for predicting high risk classical HL patients, regardless of clinical stage.
Up to 20% of Hodgkin lymphoma (HL) patients are either refractory to treatment (primary refractory) or experience relapse within four years (early relapse) of achieving complete remission (CR); this figure includes patients who experience progressive disease and patients with a particularly poor prognosis for other reasons. Only half of HL patients survive for two years if front line therapy fails, and autologous hematopoietic stem-cell transplant (ASCT) is only 50% curative. While patients in this group may benefit from analysis of the tumor-associated macrophage marker CD68, which can be used to predict adverse outcomes of cHL, the prediction is controversial.
The treatment of early-stage Hodgkin lymphoma (HL) has improved significantly, with treatment failure occurring in approximately 10% of patients. Although the therapy of advanced-stage HL has also improved, up to 10% of patients with advanced-stage HL will not achieve complete remission (CR), and 20%-30% of responding patients subsequently relapse after treatment. Salvage chemotherapy followed by autologous stem cell transplantation (ASCT) is the treatment of choice in patients with relapsed HL or if the disease is refractory to initial chemotherapy. (Kuruvilla, J. et al., Blood, 2011; 117(16): 4208-4217, at 4208.)
Prognostic factors have been identified in cohorts of patients with relapsed or refractory HL (RR-HL) who have undergone subsequent salvage chemotherapy and ASCT (summarized in Table 4). Time to relapse after initial therapy, advanced stage at relapse, and poor performance status consistently have been demonstrated to be predictors of poor outcome. (Id.)
TABLE 4Poor prognostic factors in relapsedor refractory Hodgkin lymphomaPatient groupFactorRelapsedTime to relapse <1 yearStage III-IVAnemiaB symptoms (e.g., fever, weight loss, and nightsweats)1Poor performance statusRefractoryPoor performance statusAge >50 yearsFailure to attain a temporary remissionB symptoms (e.g., fever, weight loss, and nightsweats)Stage III-IVAutologousPreviously untreated relapsestem cellResponse to chemotherapytransplantLow serum albuminAnemiaAgeLympocytopeniaB symptoms (e.g., fever, weight loss, and nightsweats)Extranodal diseaseTime to relapse <1 yearDisease status at autologous stem cell transplantDisease relapse in previous radiation field1Kurzrock, R. et al., “Serum interleukin 6 levels are elevated in lymphoma patients and correlate with survival in advanced Hodgkin's Disease and with B Symptoms.” Cancer Research, 1993; 53: 2118-2122, at 2122.(Table reproduced from: Kuruvilla, J. et al., Blood, 2011; 117 (16): 4208-4217, at 4208.)
To date, there are no reliable biomarkers to predict high risk, unfavorable, poor outcome of Hodgkin's lymphoma (HL) at the time of diagnosis or as a baseline marker. Such biomarkers would be useful (1) to provide better alternative treatment options, for example, customized/personalized dosing regimens, or (2) to spare patients from a course of treatment that has no hope of working from the onset.
Molecular abnormalities that define a disease process epitomize opportunities associated with biomarkers because these are not only a diagnostic criterion of the disease, but also are targets for therapeutic intervention and serve as quantitative measures of the disease process which can be used to monitor therapeutic response in individuals. However, such biomarkers are rare (Meyer R M, Blood May 2, 2013 vol. 121 no. 18 3541-3542). The list of cancer-related biomarkers that have predictive properties is short (Meyer R M, Blood May 2, 2013 vol. 121 no. 18 3541-3542; Dancey J E et al., Cell 2012; 148(3): 409-420; Hasenclever D. et al., N Engl J Med 1998; 339(21): 1506-1514). Those currently in use have a common feature: all either represent a molecular entity that defines the disease or are intimately involved in the mechanism of action of the targeted therapy as either a cellular membrane or intracellular signaling protein that may serve as the therapeutic agent's binding site and that affects the downstream molecular machinery that ultimately determines cancer survival (Meyer R M, Blood May 2, 2013 vol. 121 no. 18 3541-3542).
Thus far, none of the prognostic biomarkers associated with secondary biologic events, including those identified in Hodgkin's lymphoma (HL), have demonstrated predicative capacities (Steidl C. et al., J Clin Oncol 2011; 29(14): 1812-1826). For example, although CD68, a type I transmembrane protein present on monocytes, macrophages, osteoclasts, mast cells, cytoplasmic granules, activated platelets, and large lymphocytes, has been used as a biomarker for HL (See, Steidl C. et al., J Clin Oncol 2011; 29(14): 1812-1826; Table 2 at page 1818), its expression is not limited to HL, i.e., CD68 is not only expressed in anaplastic lymphomas, but is also expressed in neuroma Schwann cells, in nerves undergoing wallerian degeneration, in myeloid cell tumors and epithelial tumors.
The described invention identifies biomarkers useful in the detection of Hodgkin Lymphoma patients with poor clinical outcome, in the detection of recurrent Hodgkin lymphoma, and in the detection of evidence of metastatic Hodgkin lymphoma.
The term “FGF gene family” as used herein refers to a gene family consists of at least 23 different genes encoding related polypeptides. FGFs are expressed in almost all tissues and play important roles in a variety of normal and pathological processes, including development, wound healing and neoplastic transformation. FGFs have a broad range of biological activities that can play a role in tumorigenesis, for example, they are mitogenic for many cell types, both epithelial and mesenchymal; some FGFs, like FGF2, have potent angiogenic activity and have been implicated as promoters of tumor angiogenesis; they have been shown to increase the motility and invasiveness of a variety of cell types; and FGFs can inhibit cell death in the appropriate context. (Kwabi-Addo et al., “The role of fibroblast growth factors and their receptors in prostate cancer.” Endocrine-Related Cancer, 2004, 11:709-724, at 709-710.)
Increased Syndecan-1 (SDC-1) expression in stromal fibroblasts is observed in several carcinomas, such as those of the breast, stomach, and thyroid. In a xenograft model of human breast carcinoma cells and SDC-1-transfected fibroblasts implantation into mice, stromal SDC-1 expression was associated with significantly elevated microvessel density and larger vessel area. Expression of SDC-1 in stromal fibroblasts of human breast carcinomas also correlated significantly with high microvessel density and larger vessel area. These findings raise the possibility that SDC-1 in the reactive stroma may sequester pro-angiogenic factors and increase the local concentration of these factors to promote angiogenesis (Teng et al., “Molecular functions of syndecan-1 in disease.” Matrix Biol. 2012; 31(1):3-16.).
Tumor angiogenesis generates new vascular beds that provide nutrients and oxygen for the highly metabolic tumor mass. SDC-1 can bind to pro-angiogenic factors like FGF-2 and VEGF, and subsequently present these factors to their respective receptors on endothelial cells to initiate endothelial invasion and budding. The broader functional implications of SDC-1 in angiogenesis may also be to allow soluble SDC-1 ectodomains with bound pro-angiogenic factors to foster angiogenesis at premetastatic niches. For example, in myeloma, shedding of SDC-1 ectodomains by heparanase facilitated endothelial invasion and subsequent angiogenesis. Heparanase also upregulated HGF and VEGF in myeloma cells, and SDC-1 ectodomains bound to VEGF and presented VEGF to endothelial cells. Binding of SDC-1 ectodomains to αvβ3 and αvβ5 integrins is apparently necessary for its pro-angiogenic function, as a short inhibitory peptide that mimics the SDC-1 ectodomain endothelial cell invasion as well as tumor growth in vivo. (Teng et al., “Molecular functions of syndecan-1 in disease.” Matrix Biol. 2012; 31(1):3-16).